Retinoic acid is known to be useful for the treatment of acne. See, for example, U.S. Pat. No. 3,729,568, which discloses the use of retinoic acid compositions for the treatment of acne. Side effects associated with the use of retinoic acid, such as, for example, excessive erythema, have stimulated efforts to discover other acne treatment materials which would not have these side effects.
In order to discover such materials, the well-known ability of retinoic acid to promote increased epidermal DNA synthesis upon topical application Was utilized. This ability has been associated with the effectiveness of retinoic acid in the treatment of acne. See, for example, Christophers and Braun-Falco: Stimulation of Epidermal DNA-Synthesis with Vitamin A-Acid, Arch. Klin. exp. Derm. 232: 427-433 (1968) and Wolfe, et al.: Changes in Epidermal Differentiation After Vitamin A Acid, Arch. Klin. exp. Derm. 237: 744-795 (1970). Forty-eight novel esters and amides of all-trans-retinoic acid have been prepared and tested for their efficacy in promoting increased epidermal DNA synthesis.